The study reports the Bi³⁺ and Zn²⁺ species sorption onto various adsorbents from nitric synthetic solutions, a typical representative of waste effluents derived from non valid drugs lixiviate. Solid-liquid batch experiments carried out at 25°C to assess the adsorptive capacity of the sorbents indicate that nonliving Streptomyces rimosus biomass uptakes the metal species from solutions containing up to 100mg/l, at pH 1.9, at relatively fast kinetics. The biosorbent was loaded with about 7mg/g of Bi³⁺ and 15mg/g of Zn²⁺ after 2 hours contact time. Similar results were obtained with the mineral active carbon and the C25 strong cation exchanger. It was also found that prior treatment of the biosorbent with dilute solution of NaOH improved the sorption capacity of Bi³⁺ to up to 10mg/g. F.T.I.R spectra of the biomaterial gave bands which were assigned to potential binding groups of the amide I and amide II types, primary alcohol at C-6 and secondary alcohol at C-3. Characteristic related peaks were respectively observed at 3272-2950-2923, 1621-1536, 1010 and at 1409cm^-1. When adsorbed, both metal ions were quantitatively eluted and the biosorbent material regenerated by aqueous solutions of NaCl, 10g/l. Elution of Bi³⁺ ion was also obtained with nitric solution of Zn²⁺, 1g/l.


Keywords: Biosorption; Streptomyces rimosus; Bi³⁺; Zn²⁺



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